In a conventional vehicle performance test system, as disclosed in Patent literature 1, a vehicle mounted on a chassis dynamometer is run according to a prescribed driving mode by an automatic driving robot, and an exhaust gas discharged at that time is collected by a constant volume sampler. Then, the collected gas samples are supplied to a gas measuring device equipped with a plurality of gas analyzers for analyzing the gas samples based on different measurement principles so that each of the respective components of the gas samples is measured. Thus, the performance test of the vehicle is carried out.
The automatic driving robot is equipped with actuator parts including such as a pedal actuator for operating a pedal of the vehicle and a shift lever actuator for operating a shift lever and further equipped with a controller for controlling the actuator parts. The controller controls the actuator parts so that the vehicle is set to a given driving mode.
Here, it is considered that the controller is adapted to receive, for example, a pulse signal from a sensor part provided on, for example, a rotating drum of the chassis dynamometer based on a rotation of the rotating drum and that the controller includes a signal counting part for counting a pulse number of the pulse signal every predetermined sampling time and a control part for controlling, for example, the actuators and the like at control timings with predetermined intervals using the counted value obtained by the signal counting part. Specifically, as shown in FIG. 8, the control part is so constructed as to control the actuators at each of the control timings using the most recent (latest) counted value before the outstanding control timing in order to improve a response speed of controlling the actuators as much as possible.
However, there may be a case where the signal counting part counts not only the pulse signals from the sensor part but also noise signals such as beard-like pulse signals etc., and therefore the most recent counted value for use in generating a control signal may include the noise signal components. In such a case, the actuator parts are controlled using the counted value of the pulse signals containing the noise components, which results in a problem that the speed of the vehicle cannot be accurately controlled.